For the third day in a row, the temperature at John Glenn Columbus International Airport soared to an all-time October high temperature.
By mid-afternoon Thursday, the mercury reached 93 degrees, eclipsing the previous daily mark of 89 degrees recorded on this date in 1953 and 1898.
Wednesday’s high of 94 degrees easily surpassed the previous mark of 88 degrees set back in 1919. The average temperature on Wednesday, when combined with a morning low of 68, was the hottest October day in Columbus’ weather history dating back to 1878.
The ongoing heat had already established a new benchmark Tuesday afternoon, with a record-setting October high of 94 degrees. The former daily-record high for Oct. 1 of 89 degrees in 1952 did not stand a chance.
More impressively, the previous hottest day in October (91 degrees) on Oct. 7, 2007, was eclipsed by three degrees Tuesday and Wednesday.
The official city thermometer in Columbus has reached 90 degrees or high only seven times since records commenced — three times this week.
Record October highs were established at Cincinnati (95 degrees on Oct. 1), Dayton (94 degrees on Oct. 1-2), Mansfield (90 degrees on Oct. 1) and Zanesville (93 degrees on Oct. 3).
The heat wave is attributed to a large dome of high pressure and sinking air in the Southeast that is pumping historically warm and moderately humid air northward into the Ohio Valley and Mid-Atlantic.
A cold front will sag south late through central Ohio Thursday, after another day of unseasonable warmth in the upper 80s, bringing an end to the historic October heat wave.
The current heat wave began on the closing days of September, with highs of 91 degrees on Sept. 28 and a record-tying daily maximum of 92 degrees on Sept. 30.
September 2019 will go down as the second warmest on record (72.8 degrees in Columbus — six degrees above normal), and the ninth driest (0.85 inch — two inches below average). The month was the warmest September on record in Dayton (73.8 degrees).
Daily averages have been running about 20 degrees above normal for this time of year. Dry soils after a two-week dry spell without measurable rain contributed to the amazing warmth, because the sun’s heat was not diminished by the evaporation of surface moisture.
A dramatic shift in temperature will occur beginning on Friday. High temperatures will struggle to rise into the 60s across the northern part of the state.
The weekend will be very pleasant, with highs in the low 70s. A few showers could develop on Sunday ahead of another frontal system.
The NOAA extended outlook for the remainder of fall favors a continuation of warmer-than-normal temperatures over all, although a cool stretch of weather looms starting this weekend through next week.